Download Absorption Capability of Carbon Dioxide (CO2)

J. Appl. Environ. Biol. Sci., 4(1)94-99, 2014
ISSN: 2090-4274
© 2014, TextRoad Publication
Journal of Applied Environmental
and Biological Sciences
www.textroad.com
Absorption Capability of Carbon Dioxide (CO2)
by Algae Phylum Chlorophytain Reducing Carbon Emissions in Urban Area
Rachmat Boedisantoso1, Lancur Setoaji1, Agus Slamet1, Joni Hermana1, Driejena2
1
Laboratory of Air Pollution and Climate Change, Department of Environmental Engineering, Faculty of Civil Engineering and
Planning, Institut Teknologi Sepuluh Nopember (ITS)
2
Department of Environmental Engineering, Faculty of Civil and Environmental Engineering
Institut Teknologi Bandung (ITB)
Received: November 6 2013
Accepted: December 2 2013
ABSTRACT
Research related to the mitigation of global warming, particularly in the absorption of carbon dioxide (CO2), has become the
main focus among the scientists in the world. Carbon dioxide is naturally absorbed by green plants, sea, limestone carbonation,
and algae. Green pigment in algae or chlorophyll absorbs carbon dioxide in the photosynthesis process. Alga is suitable as
carbon sink because alga grows rapidly. This research aims to determine average uptake of carbon dioxide by algae in urban
areas and determine the effect of aeration and variation of nutrient source on algae growth. The research was conducted in a
laboratory scale unit, using reactors with a batch process. Alga used in this research was obtained from algae cultivation taken
from urban drainage. This research used two experimental variables, i.e. aeration and nutrient source. The amount of carbon
dioxide absorbed by algae was obtained by using stoichiometric ratio in the reaction of photosynthesis. Based on the
stoichiometric ratio of photosynthesis, 1 gram of algae is equivalent to 1.92 grams of absorbed CO2.Based on the research, by
adding urea fertilizer, algae absorbs 4.87 mg CO2/day in non-aerated condition or 3.84 mg CO2/day in aerated condition. While
by adding NPK fertilizer, algae absorbs 3.61 mg CO2/day in non-aerated condition or 3.01 mg CO2/day in aerated condition.
KEYWORDS—Algae, Carbon Dioxide, Carbon Sink, Global Warming.
I. INTRODUCTION
Global warming is the increase in air temperatures globally of the Earth's surface caused by rising concentrations of
greenhouse gases (GHG) which consist of CO2, CH4, NOX, SOX, and other gases in the atmosphere (Akorede et al., 2012). These
gases are emitted into the atmosphere mainly as a result of human activity. Increase in global temperature, or global warming,
causes climate change on the surface of the earth.
Carbon dioxide is naturally absorbed by green plants, sea, limestone carbonation, and algae. In the carbonation process,
carbon dioxide is used as a factor rot (Yani and Ruhimat, 2007). At sea level, especially in the polar regions that have lower
temperatures, carbon dioxide is more soluble and it will be carried away by the thermohaline circulation which brings water
masses in the heavier surface layer to the deeper water level (Janzen, 2004). In addition, green plants and algae absorb carbon
dioxide to form carbohydrates (Samudro and Mangkoedihardjo, 2006).
Green pigment in algae or chlorophyll absorbs carbon dioxide in the photosynthesis process. Each alga has a specific
growing condition so that the ability of algae to carbon dioxide uptake was different (Mulyanto, 2010). Algae growth is not only
influenced by the availability of nutrients, but it also influenced by complex interactions between physical factors such as pH,
light intensity, temperature, aeration, and biotic factors.
Domestic wastewater contains a variety of nutrients to be absorbed by the algae. Domestic wastewater in Indonesia is
usually channeled through drainage heading to rivers in urban area. It will lead to the availability of abundant nutrients in the
rivers in urban area for the growth of algae. In addition, the sources of carbon dioxide emission in urban area are more than the
sources in rural area. Therefore, urban area becomes one of the topics in this study. This research aims to determine average
uptake of carbon dioxide by algae phylum Chlorophyta in urban area and determine the effect of aeration and variation of
nutrient source on algae growth. This research can be implemented to cultivate algae obtained from waters in urban area for
further research.
II. METHOD
A. Initial Idea
Microscopic algae as plants contribute to reductions in CO2 emissions in the atmosphere. The ability of algae to
photosynthesize, like other land plants, can be used to absorb CO2. Using algae to absorb carbon dioxide becomes an alternative
in implementing carbon capture and storage technology because the amount of algae biomass is only 0.05% but the number of
terrestrial plant biomass carbon absorbed is equal with the amount of C fixed by land plants (Bishop and Davis, 2000).
* Corresponding Author:Rachmat Boedisantoso,Laboratory of Air Pollution and Climate Change, Department of Environmental
Engineering, Faculty of Civil Engineering and Planning, Institut Teknologi Sepuluh Nopember (ITS)
Email: [email protected]
94
Boedisantoso et al.,2014
B. Reactor
The reactor used in this research is made of acrylic glass shaped tube with a diameter of 14 cm. Completed picture of the
reactor can be seen in Figure 1.
Algae
Acrylic
Mixing
Electrical source
Iron
Figure 1. Rector Details.
C. Variables
Number of reactors used in this study is the result of a combination of 4 reactors and 2 reactors control variables. Total
reactors used were 6 reactors with the following details.
Reactor 1 :
Reactor 2 :
Reactor 3 :
Reactor 4 :
Reactor 5 :
Reactor 6 :
Reactor control of the water-filled drainage channels without aeration and the addition of nutrients;
Reactor control of the water-filled drainage channels with aeration, but without the addition of nutrients;
Reactor added with urea as N-ammonia source without aeration;
Reactor added with NPK fertilizer as N-nitrate source without aeration;
Reactor added with urea as N-ammonia source with aeration; and
Reactor added with NPK fertilizer as N-nitrate source with aeration.
The concentration ratio used in this research is 100: 16: 1 means C: N: P = 100: 16: 1, except for the reactor control. For the
variation of aeration, aerator used with the same type for all three reactors, including reactor control . Aeration is turned on
continuously 24 hours.
D. Parameter Analysis
The parameters analyzed in this research is the concentration of chlorophyll a (Spectrophotometric Determination of
Chlorophyll 10200), alkalinity (titration method in 2320 and 4500-CO2), MLVSS (Gravimetry Method D 2540), the
concentration of nitrate (Brucin Acetate Method), the concentration of ammonia (NesslerizationMethod ), pH (H + Electric
Method 4500), Dissolved Oxygen and temperature (Oxygen Meter Lutron DO-5510). Meanwhile, in determining the ability of
the average absorption of carbon dioxide by alga, used stoichiometric ratio on photosynthetic reactions. Carbon contained in the
carbon dioxide is directly proportional to the carbon contained in the sugar (Harjadi, 1979). Therefore, the mass of carbon
dioxide is obtained from the mass conversion of carbohydrates. By using stoichiometric ratio, it can be seen that 1 gram of
organic compounds (formed algae cells) is equivalent to 2.95 grams of CO2 absorbed.
E. The Research
The research was conducted for 24 days with each contact time is 10 days. Seeding was conducted for a week to keep the
ratio of C: N: P ideal. The ratio of C: N: P is adjusted to the desired ideal algae growth, which is 100:16:1.
Cultivated algae were added to the reactor containing water drainage. Water drainage channel which was used as a media
for algae was water drainage obtained from Jl. Arif Rahman Hakim, Surabaya. The volume of water drainage was 15 L for each
reactor. The algal cultures that were fed into the reactor were 10 L for each reactor. Thus, the ratio between algal cultures with
drainage water is 2: 3.
III. RESULTS AND DISCUSSION
A. Algae Growth and CO2 Uptake
Chlorophyll a analysis was conducted once every two days, ie on day 0, day 1, day 3, day 5, day 8, and day 10. Chlorophyll
a analysis was conducted immediately after sampling. According to Mara (2003), during the photosynthesis process algae utilize
CO2, nutrients , and sunlight reaction based on the following equation.
95
J. Appl. Environ. Biol. Sci., 4(1)94-99, 2014
106CO2 + 236H2O + 16NH4+ + HPO42-
→ C106H181O45N16P + 118O2 + 171H2O + 14H+
(1)
Based on the equation above, it can be concluded that 1 gram of new algal cell with a molecular weight of 113.5 grams of
carbon dioxide is formed by 1.92 grams of carbon dioxide. This causes algae growth charts and graphs directly proportional to
the absorption of carbon dioxide and has the same trend line. Figure 2 shows a graph of the absorption of carbon dioxide in the
non - aerated variable. While Figure 3 shows a graph of the absorption of carbon dioxide in the aerated variable.
Based on Figure 2 and Figure 3, it can be seen that the highest carbon dioxide absorption occurs in the non-aerated reactor.
On Reactor 3 (urea, non-aerated), the highest absorption of carbon dioxide reached 9.61 mg. On Reactor 4 (NPK, non-aerated)
and Reactor 1 (control, non-aerated), successive values of the highest carbon dioxide uptake were amounted to 8.33 mg and 8.97
mg.
On the reactor with aerated variable, carbon dioxide absorption is lower than reactor without aeration. For aerated variable,
the highest carbon dioxide sequestration occurs in Reactor 5 (urea, aeration), ie up to 5.77 mg. While on Reactor 6 (NPK,
aerated) and Reactor 2 (control, aerated), the highest absorption of carbon dioxide is 5.13 mg.
Figure 2. Graph of CO2 absorption by algae Phylum Chlorophyta with non-aerated variable.
Re-seeding
Figure 2. Graph of CO2 absorption by algae Phylum Chlorophyta with aerated variable.
The amount of algae in Reactor 5 (urea, aerated) is much higher than the amount of algae in the other aerated reactor. The
highest increase occurred on day 3 and day 17, ie up to 0.12 mg/L and 0.107 mg/L. On Reactor 6 (NPK, aerated), the highest
increase occurred on day 17, ie up to 0.107 mg/L. The growth of algae on Reactor 5 and reactor 6 is not much different.
However, at the first running, the amount of algae in the reactor 6 is only increased on day 1, then tend to fall until the end of the
contact time.
While the highest increase on Reactor 2 (control, aerated) occurred on day 3 and day 15, ie up to 0.107 mg/L. Based on
these data, it can be concluded that the reactor added with urea fertilizer nutrients is much better than the reactor added with
NPK fertilizer nutrients. This is because the urea with chemical formula CON2H4 has carbon elements that are also needed by the
algae. Whereas NPK fertilizer containing 15% of nitrogen nutrients in NH3, 15% of phosphorus in P2O5, and potassium in 15 %
of K2O (Hardjowigeno, 1992).
B. Alkalinity and Free Carbon Dioxide
Alkalinity determines the ability of water to support the growth of algae and other aquatic organisms. In addition, alkalinity
also acts as pH buffer. The relationship between pH, alkalinity, and factors associated with pH and water temperature were
96
Boedisantoso et al.,2014
measured subsequently multiplied by the value of the measured alkalinity as mg/L CaCO3. In equilibrium in water, carbon
dioxide can bind water to form a carbonic acid which affects the value of alkalinity in the water. Carbon dioxide and the other
three forms of alkalinity are part of an interrelated system of equilibrium. Equilibrium shift will lead to changes in ion
concentration (Sawyer et al., 2003). Figure 4 and Figure 5 shows the change in the concentration of free carbon dioxide in the
reactor.
Figure. 4. The changes of free CO2 concentration graph on non-aerated reactor.
Based on Figure 4 and Figure 5 it can be seen that free carbon dioxide at Running 1 changed fluctuatively. On day 8, the
concentration of free carbon dioxide CO2 increased to 6.66 mg/L on Reactor 3 (urea, non-aerated) and 10.38 mg CO2/L on
Reactor 4 (NPK, non-aerated). While on Reactor 1 (control, non-aeration), the concentration of free carbon dioxide decreased
until the end of the analysis period.
Figure. 5. The changes of free CO2 concentration graph on aerated reactor.
It is also occurred in the aerated reactors. On day 8, all reactors increased up to 10.44 mg CO2/L on Reactor 2 (control,
aerated); 5.99 mg CO2/L on Reactor 5 (urea, aerated), and 8.54 mg of CO2/L on Reactor 6 (NPK, aerated). Beside the increases
are caused by the alkalinity of the equilibrium reaction, these fluctuations may be caused by the fluctuations of the growth of
bacteria in the reactor. During respiration, the bacteria absorb oxygen and produce carbon dioxide. This leads to the
concentration of free carbon dioxide in the reactor was changedfluctuatively. At the Running 2, the concentration of free carbon
dioxide decreased from day 19 to day 24. This is caused by the use of carbon dioxide by algae in photosynthesis. Algae not only
utilize carbon dioxide from the ambient air, but also take advantage of free carbon dioxide contained in the water. This has led to
decrease in the concentration of free carbon dioxide in the reactor.
C. The Influence of Nutrient Source Variable
In the reactor added with urea, the absorption of carbon dioxide is higher than the absorption of carbon dioxide in the
reactor added with NPK fertilizer. On Reactor 3 (urea, non-aerated), the average amount of carbon dioxide absorbed is 4.87
mg/day. While on Reactor 4 (NPK, non-aerated), the amount of carbon dioxide absorbed is 3.61 mg/day. The difference in the
ability of carbon dioxide absorption also occurs in the aerated reactor. On Reactor 5 (urea, aerated) and Reactor 6 (NPK,
aerated), the average absorption of carbon dioxide in a row is 3.84 mg/day and 3.01 mg/day. Absorption of carbon dioxide in
Reactor 5 (urea, aerated) is higher than the absorption of carbon dioxide on Reactor 6 (NPK, aeration).
This is caused by increase of algae on Reactor 3 (urea, non-aerated) is higher than the increase of algae on the reactor 4
(NPK, non-aerated). An increasing number of different algae is caused by a type of nutrient source. Figure 6 and Figure 7 shows
97
J. Appl. Environ. Biol. Sci., 4(1)94-99, 2014
the change of ammonia concentration in each reactor.
Figure. 6. Graph of ammonia concentration in the non-aerated variables.
Figure 7. Graph of ammonia concentration in the aerated variables.
Decrease of ammonia concentration in the beginning due to significant increase in the number of algae on day 1 to day 3
after seeding. Alga uses ammonia as the primary source of N protein to build cells through photosynthesis reaction. On day 5 to
day 10 after seeding, ammonia concentrations remained decreased. This is due to the use of ammonia by algae occurs despite the
amount of algae go down. In addition due to the use of N sources by algae, ammonia reduction also occurred as a result of
nitrification to nitrate (Babu et al., 2010). Nitrification is the oxidation of ammonia to nitrate, which took place by bacteria
Nitrosomonas (Hargreaves, 1998). The change of nitrate concentrations in each reactor is shown in Figure 8 and Figure 9.
Nitrate concentration in the early contact period has decreased, but at the back end of the contact time the concentration has
increased. In the graph, the concentration of nitrate in the sample is fluctuative. Nitrate concentrations have increased from day 3
until the end of the contact time. Nitrate accumulation can be caused by inhibition of the denitrification process in the sample,
while nitrification is going well (Kaplan, 2000). Nitrification is the oxidation of ammonia to nitrite and then further oxidized to
nitrate. The rate of nitrification that occurs in the sample is higher than the rate of denitrification.
Figure.8. Graph of nitrate concentration in the non-aerated variables.
98
Boedisantoso et al.,2014
Figure.9. Graph of nitrate concentration in the aerated variables.
D. The Influence of Aeration Variable
On the aerated variable, oxygen was pumped into the reactor. Oxygen was added to provide sufficient oxygen supply for
bacterial respiration. Moreover, the addition of oxygen was also conducted in the night to reduce the competition of oxygen
uptake by algae and bacteria.
Based on the experiment that has been conducted for 24 days on three aerated reactors and three non-aerated reactors, it can
be observed that the absorption of carbon dioxide in the non-aerated reactor is higher than the absorption of carbon dioxide in the
aerated reactor. On Reactor 3 (urea, non-aeration), the average amount of carbon dioxide absorbed is 4.87 mg/day. While on
Reactor 4 (NPK, non-aerated), Reactor 5 (urea, aerated) and Reactor 6 (NPK, aerated), t the average absorption of carbon
dioxide in a row is 3.61 mg/day, 3.84 mg/day and 3.01 mg/day.
IV. CONCLUSION
The highest absorption of carbon dioxide by algae Phylum Chlorophyta occurred in the non-aerated condition by adding urea.
The absorption is up to 4.87 mg/day. On the variation of aeration, aeration does not affect the absorption of carbon dioxide by
algae. While the variation of nutrient source, adding nutrients derived from urea makes higher absorption of carbon dioxide than
the reactor adding with NPK fertilizer.
ACKNOWLEDGEMENT
L.S. thanked PT AngkasaPura II, which has provided financial support through Beasiswa Program BUMN Peduli Pendidikan
2013 and PT Pembangkitan Jawa Bali as one of the funders of this research.
REFERENCES
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
M. F. Akorede, H. Hizam, M. Z. A. AbKadir, I. Aris. dan S. D. Buba, “Mitigating The Anthropogenic Global Warming in
The Electrical Power Industry,” in Renewable and Sustainable Energy Reviews, Vol. 16 (2012) 2747-2761.
A. Yani and M. Ruhimat, GeografiMenyingkap Fenomena Geosfer. Bandung: Grafindo Media Pratama (2007).
H. H. Janzen, “Carbon Cycling in Earth Systems—A Soil Science Perspective,” in Agriculture, Ecosystems, and
Environment, Vol. 104 (2004) 399-417.
Samudro, G. and S. Mangkoedihardjo. Water equivalent method for city phytostructure of Indonesia. International Journal
of Environmental Science and Technology, 3 (3), 261-267, (2006).
A. Mulyanto, “Mikro Alga (Chlorella, sp.) sebagaiAgensiaPenambat Gas KarbonDioksida,” in Hidrosfir Indonesia, Vol. 5,
No. 2 (2010) 13-23.
J. K. B. Bishop and R. E. Davis, Autonomous Observing Strategis for The Ocean Carbon Cycle. Lawrence Berkeley
National Laboratory (2000) Paper LBNL.
American Public Health Association, Standard Method for Examination of Water and Wastewater. American Water Work
Association, Water Environment Federation (2005).
S. S. Harjadi, PengantarAgronomi. Jakarta: GramediaPustakaUtama (1979).
D. Mara, Domestic Wastewater Treatment in Developing Countries. Trowbridge: Cromwell Press (2003).
H. S. Hardjowigeno, Ilmu Tanah. Jakarta: PT Melton Putra (1992).
C. N. Sawyer, P. L. McCarty, and G. F. Parkin, Chemistry for Environmental Engineering and Science Fifth Edition.
Singapore: McGraw-Hill (2003).
M. A. Babu, M. A. Hes, N. P. van der Steen, C. M. Hooijmans, and H. J. Gijzen, “Nitrification Rates of Algal-Bacterial
Biofilms in Wastewater Stabilization Ponds under Light and Dark Conditions,” in Ecological Engineering, Vol. 36 No. 12
(2010) 1741-1746.
J. A. Hargreaves, “Nitrogen Biogeochemistry of Aquaculture Ponds,” in Aquaculture, Vol. 166 No. 3-4 (1998) 181-212.
D. Kaplan, R. Wilhelm, and A. Abeliovich, “Interdependent Environmental Factors Controlling Nitrification in Waters,” in
Water Science and Technology, Vol. 42 No. 1-2 (2000) 167-172.
99